Drinking straw

ABSTRACT

A reusable drinking straw has a metal tubular body with a first cylindrical segment at one free end, a second cylindrical segment at the opposite free end and a corrugated segment between the first and second segments. The cross-section of the opening of the drinking end is smaller than the cross-section of the tubular body and is preferably oval-shaped.

The invention relates to a drinking straw comprising a tubular base body having at one free end a first cylindrical segment and at the other free end a second cylindrical segment, wherein a third segment is formed as a corrugated tube and is arranged between the first segment and the second segment.

Such drinking straws are generally known and are used to drink beverages from bottles or jars. Currently, drinking straws are mostly made of plastic, which are disposable articles. In order to be able to use drinking straws multiple times, it is already known to manufacture drinking straws from a metallic material. US 2015/0190004 A1 and US 2019/0099025 A1 show drinking straws made of a metallic material. The drinking straw known from US 2015/0190004 A1 is designed in a cylindrical shape, wherein one segment can be designed as an arc. The shape of the drinking straw is not variable and therefore cannot be adapted to different liquid containers, for example. The drinking straw known from US 2019/0099025 A1, on the other hand, is designed as a corrugated tube over its entire length and can be shaped into any desired shape. However, the problem with this drinking straw is that it is difficult to shape the straw into a desired shape in such a way that the straw retains the shape, due to its great flexibility.

The invention is based on the object of providing a drinking straw which can be reused multiple times and which has improved usage characteristics.

This object is solved with the characteristics of claim 1. The subclaims refer to advantageous embodiments.

The drinking straw according to the invention comprises a tubular base body of metallic material, which has a first cylindrical segment at one free end and a second cylindrical segment at the other free end, wherein a third segment formed as a corrugated tube is arranged between the first segment and the second segment, wherein the first segment, the second segment and the third segment are made of the same material and formed in one piece and wherein the free end formed from the first segment forms a drinking opening, wherein the cross-section of the drinking opening is smaller than the cross-section of the base body.

Thus, the drinking straw according to the invention has the shape of a flexible plastic drinking straw. However, the drinking straw according to the invention is made of metallic material and can therefore be reused multiple times. The first segment and the second segment are formed in a cylindrical respectively tubular manner and are rigid. Only the third segment arranged between the first segment and the second segment, designed as a corrugated tube, is flexible. By bending the third segment, the second segment can be angled relative to the first segment, which improves the straw's usage characteristics. According to the invention, the drinking straw is made of the same material and is designed in one piece so that it is easy to manufacture and hygienic to operate. The shape of the drinking opening, which deviates from the tubular base body and has a smaller cross-section, makes it possible to influence the volume flow of the liquid flowing through the drinking opening. This makes it also possible to comfortably use drinking straws with larger diameters.

Preferably, the drinking opening is oval-shaped. The achieved flattening compared to the circular base body reduces the cross-section of the drinking opening, which is accompanied by a reduction in the volume flow. A larger suction pressure is required to achieve a constant volume flow.

Preferably, the base body is made of stainless steel. Stainless steel is tasteless and insensitive to the acids found in many beverages. Furthermore, a drinking straw made of stainless steel can be hygienically cleaned at high temperatures.

The third segment can be created by compressing. During the production of the drinking straw, the first segment and the second segment are moved towards each other, whereby the tubular base body is corrugated in the area of the third segment. This makes the third segment flexible so that it can be bent repeatedly in different directions without breaking the base body.

Alternatively, the third segment can be created by rolling. In this context, it is particularly conceivable that the third segment is thread-shaped. Tools can be used to roll threads into cylindrical rods. Such tools include thread rollers, for example. Rolling is particularly advantageous with small diameters, as the free cross-section of small diameters would be reduced too much during the compression process. Rolling, on the other hand, only leads to a slight reduction in the inner diameter.

The wall thickness of the base body can be between 0.15 mm and 0.3 mm. Preferably the wall thickness of the base body is 0.2 mm. As a result, the drinking straw has a very low wall thickness, especially with regard to the metallic drinking straws known from the prior art. This inventive wall thickness is particularly advantageous with regard to the corrugated third segment, because the low wall thickness makes it possible to bend the third segment several times with little force.

The ratio of the outer diameter of the third segment to the outer diameter of the first segment and the second segment may be between 1.1 and 1.75. The outer diameter of the first segment and the second segment can be between 5 mm and 15 mm. For example, if the outer diameter of the first segment and the second segment is 10 mm, the outer diameter of the third segment is between 12.5 mm and 17.5 mm. With this diameter ratio, the straw is easy to use and remains in the desired position after bending.

The ratio of the inner diameter of the third segment to the inner diameter of the first segment and the second segment is preferably between 0.75 and 1.5. With this embodiment, the inner diameter is almost constant across all segments, although the third segment is corrugated. This enables a barrier-free flow through the drinking straw. In the course of compressing, the third segment is mainly deformed radially outwards.

The straw has particularly advantageous usage characteristics when the third segment has between 10 and 15 projections that protrude radially outward.

In case of an alternative embodiment, the ratio of the outer diameter of the third segment to the outer diameter of the first segment and the second segment may be between 0.75 and 1.5. The ratio of the inner diameter of the third segment to the inner diameter of the first segment and the second segment is preferably between 0.5 and 0.9 with this alternative embodiment. The advantage of this embodiment is that it produces an even outer contour. This is particularly advantageous if the base body is designed with a smaller outer diameter between 4 mm and 8 mm.

Preferably, the first segment is three times longer than the second segment.

Some embodiments of the drinking straw according to the invention are explained below by means of the figures. The figures show, each schematically:

FIG. 1 a drinking straw with a larger diameter;

FIG. 2 the drinking straw according to FIG. 1 with modified drinking opening;

FIG. 3 an alternatively designed drinking straw with a smaller diameter;

FIG. 4 an alternatively designed drinking straw with a rounded drinking opening.

The figures show a drinking straw 1, comprising a tubular base body 2 made of metallic material, here made of stainless steel. The base body 2 has a first cylindrical segment 3 at one free end and a second cylindrical segment 4 at the other free end. Between the first segment 3 and the second segment 4, there is a third segment 5 formed as a corrugated tube.

The first segment 3, the second segment 4 and the third segment 5 are made of the same material and formed in one piece.

In the embodiment according to FIG. 1 , the third segment 5 is created by compression. Due to the compression, the ratio of the outer diameter of the third segment 5 to the outer diameters of the first segment 3 and the second segment 4 is 1.5.

The outer diameter of the first segment 3 and the second segment 4 is 8 mm for the embodiment shown in FIG. 1 . Accordingly, the outer diameter of the third segment 5 is 12 mm.

For the embodiment shown in FIG. 1 , the ratio of the inner diameter of the third segment 5 to the inner diameter of the first segment 3 and the second segment 4 is 1. The inner diameter of the three segments 3, 4, 5 is 7.6 mm. This results in a wall thickness of the base body 2 of 0.2 mm. The third segment 5 has 12 radially outwardly protruding, essentially semi-circular projections 6, which form a corrugated tube. FIG. 1 shows in the lower illustration the drinking straw 1 in top view and shows in the upper illustration in detail an enlargement of the third segment 5.

With regard to the dimensions, the embodiment according to FIG. 2 is based on the embodiment according to FIG. 1 . The embodiment according to FIG. 2 has a drinking opening 7 at the free end. The cross-section of the drinking opening 7 differs from the cross-section of the base body 2 and is smaller. In this embodiment, the drinking opening 7 is oval-shaped, i.e. flattened compared to the cylindrical base body 2. With a diameter of 8 mm, the cross-sectional area of the first segment 3 is about 50 mm². In the case of ovalization, where one half axis has a length of 4 mm and the other half axis a length of 2 mm, the cross-sectional area is only 25 mm². FIG. 2 shows three views of drinking straw 1, with the upper illustration showing the drinking straw 1 in side view, the middle illustration showing the drinking straw 1 in top view and the lower illustration showing the drinking straw 1 in spatial view.

For the embodiment according to FIG. 3 , the ratio of the inner diameter of the third segment 5 to the inner diameter of the first segment 3 and the second segment 4 is 0.86. The inner diameter of the first segment 3 and the second segment 4 is 3 mm. Thus, the inner diameter of the third segment 5 is 2.6 mm. The wall thickness of the base body 2 is 0.2 mm. The third segment 5 has an inwardly protruding projection 6 in the form of a helical line which forms a corrugated tube. The projection 6 is produced by rolling on a thread roller. FIG. 3 shows in the lower illustration the drinking straw 1 in the top view and in the upper illustration in detail an enlargement of the third segment 5.

For the embodiment according to FIG. 4 , the drinking opening 7 is provided with a rounded edge. For this, the free end of the drinking opening 7 is bent inward and is shaped in the form of a quarter circle. The radius of the quarter circle is 0.5 mm. This design results in a more comfortable use. It can be avoided that the drinking straw has a sharp edge on the side of the drinking opening 7. The outer diameter of the first segment 3 and the second segment 4 is 8 mm for the embodiment shown in FIG. 1 . Accordingly, the outer diameter of the third segment 5 is 12 mm. The ratio of the inner diameter of the third segment 5 to the inner diameter of the first segment 3 and the second segment 4 is 1. The inner diameter of the three segments 3, 4, 5 is 7.6 mm. This results in a wall thickness of the base body 2 of 0.2 mm. The third segment 5 has 12 radially outwardly protruding, essentially semi-circular projections 6, which form a corrugated tube. 

What is claimed is:
 1. A drinking straw, comprising a tubular base body of metallic material, which has a first cylindrical segment at one free end and a second cylindrical segment at the other free end, wherein a third segment formed as a corrugated tube is arranged between the first segment and the second segment, wherein the first segment, the second segment and the third segment are made of the same material and formed in one piece and wherein the free end formed from the first segment forms a drinking opening, wherein the cross-section of the drinking opening is smaller than the cross-section of the base body.
 2. The drinking straw according to claim 1, wherein the drinking opening is provided with a rounded edge.
 3. The drinking straw according to claim 2, wherein the free end of the drinking opening is bent inward.
 4. The drinking straw according to claim 3, wherein the free end of the drinking opening is shaped in the form of a quarter circle.
 5. The drinking straw according to claim 4, wherein the radius of the quarter circle is between 0.2 mm and 1 mm.
 6. The drinking straw according to claim 1, wherein the wall thickness of the base body is between 0.15 mm and 0.3 mm.
 7. The drinking straw according to claim 1, wherein the drinking opening is oval-shaped.
 8. The drinking straw according to claim 1, wherein the base body is formed of stainless steel.
 9. The drinking straw according to claim 1, wherein the third segment is produced by compressing or rolling.
 10. The drinking straw according to claim 1, wherein the outer diameter of the first segment is between 5 mm and 15 mm.
 11. The drinking straw according to claim 1, wherein the ratio of outer diameter of the third segment to outer diameter of the first segment and the second segment is between 1.1 and 1.75.
 12. The drinking straw according to claim 1, wherein the ratio of the inner diameter of the third segment to the inner diameter of the first segment and the second segment is between 0.75 and 1.5.
 13. The drinking straw according to claim 1, wherein the third segment has between 10 and 15 radially outward protruding projections.
 14. The drinking straw according to claim 1, wherein the ratio of outer diameter of the third segment to outer diameter of the first segment and the second segment is between 0.9 and 1.1.
 15. The drinking straw according to claim 14, wherein the ratio of the inner diameter of the third segment to the inner diameter of the first segment and the second segment is between 0.5 and 0.9. 